1. Field of the Invention
This invention relates to a display device with touch panel.
2. Description of the Related Art
Touch panels as input devices provided on display screens of information communication terminals including computers have been widely used.
The touch panels are input devices that allow processors to perform processing by recognizing coordinates on panels touched by users using fingers or the like. For the touch panels, a resistive-film system that detects changes in resistance of a touched part, an optical sensor system that detects changes in amounts of light of a part blocked by touch, a capacitance coupling system that detects changes in capacitance, etc. have been known. The capacitance coupling system has been widely used because of the higher transmittance of the panel without reduction in the display image quality, no contact with other electrodes and the higher durability, or the like.
Recently, in response to requests for downsizing and thinning with respect to information communication terminals, thinner liquid crystal display devices with touch panel have been demanded. JP 2009-244958 A has disclosed a thinner liquid crystal display device with touch panel by using common electrodes of the liquid crystal display device as drive electrodes of the touch panel in the IPS (In-Plane Switching) liquid crystal display device in which both pixel electrodes and the common electrodes are provided on a TFT (Thin Film Transistor) substrate.